1. Field of Invention
The invention relates to an electrophoresis (EP) detection system for detecting fluorescent EP and, in particular, to a cost-effective micro fluorescent EP detection system of a small size for the convenience of carrying.
2. Related Art
Due to its ionization or charged particles attached thereon, any substance in an electric field will move toward a specific pole. The charged particles may be small ions or large biological molecules such as proteins, nucleus acid, viruses, or cells. The amino acid units that make up a protein are bipolar objects, which can be ionized and become a charge source under a certain pH environment. Charged particles under an electric field move toward the pole with the opposite polarity. This phenomenon is called electrophoresis (EP). In 1937, a Sweden scientist Tiselius invented the first EP device in the world and established the moving boundary EP method. Since there is a density change and therefore convection in the heated free solution in the moving boundary EP method, the initial region is disturbed and hard to distinguish. Moreover, the EP device is very expensive and it is hard to make it popular. In 1950s, people haven been improving the EP device and searching for better filter papers, cellulose acetate membranes, starch and agarose as the supporting mediator. In 1960s, polyacrylamide is found to be the supporting mediator and scientists had developed SDS-polyacrylamide EP, equal-potential EP, two-way EP, and print transfer EP techniques. These techniques have the advantages of simple equipment, convenient operations, and high distinction abilities. Currently, the EP technique has become an indispensable tool for biochemistry, immunology, molecular biology, and closely related medical sciences, agriculture, pharmacology and certain engineering analyses.
For example, the U.S. Pat. No. 5,885,430, “Capillary tube holder for an electrophoretic apparatus,” utilizes the electric field strength change to increase of decrease the density of a probed solution. A laser beam is then shined on the probed solution to excite its fluorescent reaction. Such reaction information is then collected and processed to send out a signal for further analysis. However, its light-emitting part and the light-receiving part are not integrated. Not only does the system volume become too large, using laser as the light source is also very power consuming. It is almost impossible to meet the market demand for a compact device and the environmentally friendly consideration. Furthermore, the signal processing is very complicated. Its data analysis is quite time-consuming and thus lowers the detection efficiency.